Density functional theory study of efficient electrocatalytic activity for CO₂RR to C1 products on TM-C₃N₃

Due to its pre-site activity and excellent catalytic activity, Metal–Nitrogen–Carbon (M–N–C) are considered as efficient electrocatalytic CO₂RR catalysts. Herein, density functional theory (DFT) is utilized to calculate and screen the thermodynamic stability of 3d transition metal atoms (TM) embedded in C₃N₃ (TM-C₃N₃). The adsorption performance and electron transfer of CO₂ on TM-C₃N₃ were analyzed. Fe-C₃N₃ demonstrates high efficiency in the reduction process of CO₂ to HCOOH, requiring a low limiting potential (U_L), under the condition of adding an implicit solvent model, the catalytic activity of Fe-C₃N₃ becomes better. The activity of reducing CO₂ to CH₄ on V-C₃N₃ is excellent. At the same time, V-C₃N₃ and Fe-C₃N₃ can effectively inhibit the occurrence of HER. Novel linear relationships of catalysts electrocatalyze CO₂ to HCOOH and CH₄ have been discovered. The changes of catalysts’ activity and selectivity in the presence of applied voltage were also demonstrated. In addition, the possibility of other products (CO, CH₃OH,) and pathways for CO₂ reduction were also analyzed.